Maximization of User’s Fairness in an imbalance-NOMA Network scenario with more far users, by means of multiple near-field Relays.

The development of 5G networks is currently prominent in the mobile network industry. This is due to the need for increased network performances, such as more capacity and reliability (users’ fairness); which the current 4G networks fall short of delivering. Non-Orthogonal Multiple Access (NOMA) technology has been identified by others, as key elements for the realization of 5G networks; thus, the design of NOMA networks has recently gained popularity. NOMA technology implies serving 2 or more users in the same frequency band and discriminating their respective information by assigning different power levels to each (PD-NOMA). In the case of 2 users per frequency band, a base-station with N-antennas must serve 2N users at the time. Initial works in the NOMA-networks’ design often assumed that the 2N-users to be served consist of N-far field users and N-near field users. This scenario is referred to as the “balanced-NOMA” scenario. Initial power-allocation algorithms (Initial FM-PAA) have been proposed to maximize users’ fairness of NOMA networks in this scenario, and have yielded relatively good results. However, there can be a case where there are more far-users than near-users in the 2N set to be served; it is referred to as an “imbalanced NOMA” scenario. In this case, if the “initial FM-PAA” is used straight, it will only serve possible pairs, leaving many far-users unserved. This will result in very poor user fairness for the network and that of cell-edge users.

The research is intended to maximizes both user and system fairness especially with those users at the cell-edge, by utilizing MATLAB platform, the proposed advance "PAA" has shown significant performance compared to the existing and initial algorithms.